Good point, we'll have to see. I have the same problem as the GP (though up to 50 tabs usually) and indeed "bookmark all"+"close all" doesn't really help because if you never review those bookmarks, you tend not to take the step either.
As someone else itt already said, a better solution would be some improved bookmarking system that I can use to just file away a tab, knowing that it'll be there when I need it, as well as offering the option of, I dunno popping up for review in a couple of days or a specific time maybe.
One thing I do not understand is why modern browsers, apart from bookmark-folders do not offer tags as well. They were a hugely successful way of ordering things back in the day and they have all but disappeared for some reason. And they would be tremendously useful in bookmarks (to me). And del.icio.us is dead, plus I don't want a web service to keep my bookmarks, it's too slow.